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  • 1
    Electronic Resource
    Electronic Resource
    Lichtabsorption aromatischer Kohlenwasserstoffe (1947)
    Springer
    Naturwissenschaften 34 (1947), S. 124-125 
    Details
    ISSN: 1432-1904
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00602643
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  • 2
    Electronic Resource
    Electronic Resource
    Electronic and magnetic structure of the polymeric system di-imidazolato iron(II) (1976)
    Springer
    Theoretical chemistry accounts 41 (1976), S. 223-232 
    Details
    ISSN: 1432-2234
    Keywords: Mössbauer spectroscopy ; Thermogravimetry ; Di-imidazolato iron(II)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The polymeric system di-imidazolato iron(II) is synthesized from the reaction of either ferrocene or cyclopentadienyl-irondicarbonyl with imidazole. From Mössbauer measurements in the temperature range 4.2 K⩽T⩽448 K we find two different iron sites in the compound, denoted byA andB, respectively with ratio [A]/[B] = 1.79±0.03. From the isomer shift values we conclude that both Fe A and Fe B are in the ferrous high-spin state. Below 13.95±0.10 K both subspectra are considerably broadened due to magnetic ordering. From the analysis of the magnetic spectra we derive for the main componentV zz of the electric field gradient tensorV zz A 〉0 andV zz B 〈0. Additionally, we investigate the thermal decomposition of the compound by thermogravimetry in the temperature range 20 °C⩽T⩽ 750 °C and by Mössbauer spectroscopy in the temperature range 20 °C⩽T⩽505 °C. The decomposition takes place in four steps. The first step between 20 °C and 190 °C is due to the loss of imidazole nonbonded to iron(II). Comparing the amount of iron with that of pure imidazolato iron(II) we find the formula FeIz2+0.70 (±0.02) IzH, with Iz standing for doubly deprotonated and IzH for deprotonated imidazole. Step 2 (193 °C〈T〈235 °C) and step 3 (400 °C〈T〈500 °C) are found from both methods. Step 4 is above 500 °C. Heat treatment and vacuum conditions affect the thermal decomposition products. Isomer shifts δ A and δ B , and temperature dependent quadrupole splittings ΔE Q A and ΔE Q B are explained using a simple ligand field picture for orbital splittings and occupancies of quasi-tetrahedrally (A) and quasi-octahedrally (B) coordinated ferrous high-spin compounds. Using finally the experimental ratio [A]/[B] = 1.79 we derive for the over-all chemical formula (1.79 Fe A Iz4/2+Fe B Iz4/2+2 IzH) n = (FeIz2+0.71 Iz) −n in agreement with the result which we derived from investigating the thermal decomposition of our compound.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01151957
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  • 3
    Electronic Resource
    Electronic Resource
    Electronic and magnetic structure of the polymeric system di-imidazolato iron(II) (1976)
    Springer
    Theoretical chemistry accounts 41 (1976), S. 233-241 
    Details
    ISSN: 1432-2234
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract For the Fe-derivatives of 2-methyl-, 2-ethyl-, and 2-phenyl-imidazoles Mössbauer spectra are measured in the temperature range 4.2 K⩽T⩽300 K. Their computer analysis yields isomer shifts δ, quadrupole splittings gDE Q, asymmetry parameters η, line widths Γ, internal magnetic fieldsH int, sign of the main componentV zz of the electric field gradient tensor, and angle ζ between $$\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\rightharpoonup}$}} {H} ^{\operatorname{int} } $$ and $$\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\rightharpoonup}$}} {V} _{zz} $$ . We find that the substituents methyl, ethyl, and phenyl have significant influence upon these parameters, i.e. upon electronic structure and magnetic ordering; onlyV zz〉0 and η=0 are the same for all compounds. The δ- and ΔE Q-values indicate that the iron is in the ferrous high-spin state and tetrahedrally coordinated by imidazole nitrogens. The conclusion that the compounds are three-dimensional coordination polymers is drawn from their magnetic ordering at low temperatures. Transition temperatures areT methyl * =33.25±0.05 K,T ethyl * =30.5±0.05 K, andT phenyl * =25.7±0.05 K. Assuming a power-law dependence forH int of the formH int =H(4.2)D(1-T/T*)β we deriveD= 1.52±0.05 and β = 0.31±0.03 for the three compounds. From the discussion of the saturation value of the internal magnetic fieldH int (4.2 K) we derive for the methyl- and phenyl-compound ground state and first excited state single-electron wave function |n〉=a|x 2−y 2〉+b|xy〉+c|3z 2−r 2〉+d|xz〉+e|yz〉+lig. and |K〉=a′|x 2−y 2〉+b′xy〉+c ′|3z 2−r 2〉+d′|xz+e′|yz〉+lig, respectively, and energy separationsE k-E n, specified by: 0.88⩽b⩽0.92, 0.27⩽c⩽0.39, 0.55⩽a′⩽0.57, −0.32⩽b′⩽−0.22, 0.69=⩽c′⩽0.77,a =d=e =d′ =e′ = 0,E k-E n = 4000±500 cm−1 for the methyl compound, and 0.92⩽b⩽0.96, 0⩽c⩽0.27, 0.49 ⩽a′ ⩽0.52, 0.76 ⩽c′⩽0.84,a =d=e =b′ =d′ =e′ = 0,E k-E n = 4000±500 cm−1 for the phenyl compound. The coefficientsa, h.,e′ are approximate values mainly due to the assumption of isotropic covalency, due to the lack of better knowledge of the energy separationE k —E n, and due to the approximative procedure of estimating the orbital contribution toH int. The situation for the ethyl compound is less transparent because of the non-collinearity of $$\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\rightharpoonup}$}} {H} ^{\operatorname{int} } $$ and $$\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\rightharpoonup}$}} {V} _{zz} $$ in this case.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01151958
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  • 4
    Electronic Resource
    Electronic Resource
    Dieisen(III)-hexacyanoferrat(II)-oxid (1987)
    Springer
    Monatshefte für Chemie 118 (1987), S. 203-209 
    Details
    ISSN: 1434-4475
    Keywords: Di-iron(III)-hexacyanoferrate(II)-oxide ; Oxygen absorption ; Semiconductors, Mössbauer-spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The title compound3 has been obtained through the action of molecular oxygen upon di-iron(II)-hexacyanoferrate(II)1 which has been prepared by thermal decomposition of ammonium hexacyanoferrate(II)2 in vacuum.2 und3 have been characterized by analytical methods andMössbauer-spectroscopy.3 and the analogous halogen compounds are semiconductors with a conductivity of 2 to 5 · 10−5 S/cm.2 is ideally suited for the quantitative absorption of oxygen from water and organic solvents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00810053
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  • 5
    Electronic Resource
    Electronic Resource
    Über Fluorsulfinsäureester (Alkylfluorosulfite) (1969)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 102 (1969), S. 443-448 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch Umsetzung der Chlorsulfinsäureester der C1- bis C4-Alkohole mit Kaliumfluorosulfit wurden die entsprechenden Ester der Fluorsulfinsäure 1a bis 7a dargestellt und insbesondere NMR-spektroskopisch charakterisiert. Die Fluorverbindungen sind thermisch beständiger als die Chlorverbindungen. Durch Wasser, Lewis-Säuren und in Glasgefäßen werden die Alkylfluorosulfite zersetzt. Mit Trimethylamin reagieren die Ester zu quartären Ammoniumfluorosulfiten. Verbindungen mit anionaktivem Chlor tauschen mit Alkylfluorosulfiten das Halogen aus.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19691020211
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  • 6
    Electronic Resource
    Electronic Resource
    Notiz über die Umsetzung von Dimethylchlorphosphin mit Dimethylphosphinoxid (1971)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 2972-2974 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19711040939
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  • 7
    Electronic Resource
    Electronic Resource
    Notiz über Tetramethyldiphosphiniumchlorid und Dimethylphosphoniumchlorid (1971)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 2967-2971 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19711040938
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  • 8
    Electronic Resource
    Electronic Resource
    Umsetzung des Chlordimethylphosphans mit Trimethylphosphan, Monomethylphosphan und Phosphan (1979)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 2278-2281 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Chlorodimethylphosphane with Trimethylphosphane, Monomethylphosphane, and PhosphaneCompleting a previous investigation2), this paper gives evidence that dialkylchlorophosphanes generally react with tertiary and secondary phosphanes to yield penta- and tetraalkyldiphosphonium chlorides ([P2R5]+Cl-, [P2R4H]+Cl-), whereas primary phosphanes give polymer or cyclic phosphanes (PR)n and dialkylphosphonium chlorides [R2PH2]+Cl- Phosphane, PH3, is converted into polymer (PH)x.
    Notes: Eine frühere Untersuchung2) fortsetzend konnten wir am Beispiel der Methylverbindungen bestätigen, daß Dialkylchlorphosphane mit tertiären und sekundären Phosphanen unter Bildung von Penta- und Tetraalkyldiphosphonium-chloriden ([P2R5H]+Cl- [P2R4H]+Cl-) reagieren, während primäre Phosphane polymere oder cyclische Phosphane (PR)n und Dialkylphosphonium-chloride [R2PH2]+Cl- ergeben. Phosphan, PH3, wird in polymeres Phosphan (PH)x umgewandelt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19791120633
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  • 9
    Electronic Resource
    Electronic Resource
    1.2-Difluor-disulfan-1.1-difluorid und 1-Fluor-2-chlor-disulfan-1.1-difluoridÜber die Ergebnisse dieser Untersuchungen ist erstmals am 21. Juli 1969 während des 5. Internationalen Symposiums über Fluorchemie vorgetragen worden. (1970)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1701-1708 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1.2-Difluorodisulfane 1.1-Difluoride and 1-Fluoro-1-chlorodisulfane 1.1-DifluorideN.m.r., i.r., and mass spectrometric data support the existence of two new sulfur-fluorine compounds SF3SF (1) and SF3SCl (2) of low stability, which can be regarded as a dimer of SF2 and an adduct of SF2 and SFCl. Besides the products of their decomposition SF4, S2F2, S2FCl, S2Cl2), and sulfur, the compounds may be obtained in low yield by the reaction of sulfur dichloride with active potassium fluoride under proper conditions.
    Notes: NMR-, IR- und massenspektroskopische Untersuchungsergebnisse weisen auf die Existenz zweier unbeständiger, bisher unbekannter Schwefel-Fluor-Verbindungen SF3SF (1) und SF3SCl (2), die als dimeres SF2 und Additionsprodukt aus SF2 und SFCl angesehen werden können. Die Verbindungen können in geringer Ausbeute neben ihren Zersetzungsprodukten SF4, S2F2, S2FCl, S2Cl2 und Schwefel durch Umsetzung von Schwefeldichlorid mit aktivem Kaliumfluorid unter geeigneten Bedingungen erhalten werden.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19701030606
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  • 10
    Electronic Resource
    Electronic Resource
    Über die (Dimethylamido)dithiomethylphosphonsäure und ihre Salze (1980)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 1837-1846 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Formation and Characterization of (Dimethylamido)dithiomethylphosphonic Acid and its SaltsThe title compound 3, which exhibits a betaine-like structure, and its metal derivatives (Cu, Ag, Tl)L, (Co, Ni, Zn, Cd)L2, NiL2·2Py, and CoL3 (L = anion of 3) have been obtained from the dimethylammonium salt 2, which is readily accessible from 3 and dimethylamine. The crystal structure of NiL2 (9) was solved with X-ray diffraction data. In an aqueous solution, 2 is oxidised by iodine to give the sulfane derivative 21. Hydrogen sulfide, hydrogen selenide and methylmer-captan readily substitute the dimethylamino group of 2 to yield the dimethylammonium salts 22,23,24 of trithio-, dithioseleno-, and methyl trithiomethylphosphonic acids.
    Notes: Die Titelverbindung 3, die eine betain-artige Struktur besitzt, und ihre Metallderivate (Cu, Ag, Tl)L, (Co, Ni, Zn, Cd)L2, NiL2·2Py und CoL3 (L = Anion von 3) wurden aus dem Dimethylammonium-Salz 2 dargestellt, das leicht aus 1 und Dimethylamin zu erhalten ist. Die Kristallstruktur von NiL2 (9) wurde aus Röntgenbeugungsdaten ermittelt. 2 wird in wäßriger Lösung durch Iod zum Disulfanderivat 21 oxidiert. Schwefel- bzw. Selenwasserstoff und Methylmercaptan verdrängen die Dimethylaminogruppe von 2 unter Bildung der Dimethylammonium-salze 22, 23, 24 der Trithio-, Dithioseleno- und Methyl-trithiomethylphosphonsäure.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19801130519
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